1996 Chevrolet Astro Brake Service (ONLINE REPAIR MANUALS)

Removal

• Siphon ^2/3 of brake fluid from master cylinder reservoir serving front disc brakes.
• Raise vehicle, support on jack stands and remove front wheels.
• Bottom caliper piston in bore. Insert a screwdriver between inboard shoe and piston, then pry piston back into bore. The piston can also be bottomed in the bore with a large C-clamp, Fig. .
• Remove support key retaining screw.
• Drive caliper support key and spring from steering knuckle with a suitable drift and hammer, Fig. .
• Lift caliper from anchor plate and off rotor, Fig. . Hang caliper from coil spring with wire. Do not allow cal...

Disassemble

• Place accumulator compressor tool No. J-26889 or equivalent, around end of accumulator.
• Install nut onto stud as shown in Fig. , then depress the accumulator with a C-clamp.
• Remove retainer by using a punch.
• Release C-clamp and remove accumulator compressor tool.
• Remove accumulator, O-ring, retainer, plug and spring, Fig. .
• Remove retainer, output pushrod, baffle, piston return spring and retainer.
• Using a suitable saw, cut off eyelet of pedal rod, then remove the boot.
• Remove nut, bracket and bolts, then separate cover from housing.
• Remove piston assembly and seals...

General Service Precautions

Avoid contact with brake fluid when servicing the anti-lock brake syste...

Height Sensing Proportioning Valve

The height sensing proportioning valve must be adjusted whenever the valve and/or linkage is disassembled or removed for service. In addition, adjustment should be checked if excessive front wheel lock-up is experienced with a lower than desired brake application rate when vehicle is at or near maximum GVWR.

• Raise and support vehicle leaving wheels on, and allow axle to hang freely.
• Remove lever retaining nut and disconnect lever from valve shaft, Fig. .
• Rotate valve shaft to permit installation of correct adjustment gauge, Fig. , ensuring that D shape...

The braking system can be bled manually or with pressure bleeding equipment. If bleeding manually, check fluid level frequently.

Brake fluid should never be reused. Before driving the vehicle, check brake operation to ensure a firm pedal has been obtained.

Brake fluid will damage electrical connections and painted surfaces. Use shop cloths, suitable containers, and fender covers to prevent brake fluid from contacting these areas. Always seal and wipe off brake fluid containers to prevent spills.

Manual Bleeding

C/K, G, M/L, P & S/T Series

• If vehicle is equipped with a vacuum or hy...

Delco-Moraine Master Cylinder

Composite Type

When performing the following procedures, refer to Fig. for all models except Lumina APV, Silhouette & Trans Sport, noting that the composite reservoir may vary in design. Refer to Fig. for Lumina APV, Silhouette & Trans Sport models.

Disassemble

• Remove master cylinder from vehicle.
• Remove reservoir cover and diaphragm. Discard old brake fluid in reservoir.
• Inspect cover and diaphragm. Replace if cut, cracked or deformed.
• Remove fluid level switch and proportioning valve assembly, if equipped.
• Depress primary piston and remove lock ring.
• P...